Mutsu-Hatakeyama held Nihonmatsu Castle saw its power gradually diminish over the course of the Sengoku period, becoming vassals of the Ashina clan. The Mutsu-Hatakeyama
Japan. Throughout most of the Edo period, Nihonmatsu Castle was home to the Niwa clan, daimyō of Nihonmatsu Domain. The castle was also known as "Kasumi-ga-jō"
became the head of the Date clan in 1584, two years after the death of Oda Nobunaga, destroyed the Nihonmatsuclan and other clans, and then in 1589, at the